How times have changed. In 2007 the IPCC seemed to be 90% confident that the world would warm by about 0.4 degrees over the next two decades. Now Brian Schmidt braves up to offer a bet of “anything above zero”. Is he really a sceptic? It appears so.

How much should we pay now to prevent “any warming above zero” in the next twenty years? $4.5 billion a year? How about nothing."